A Scientist Thinks Brain Fog and Anxiety May Reflect Energy Rationing
At a mitochondria symposium, Columbia researcher Martin Picard used his own nerves to illustrate his hypothesis that mental strain carries an energy cost.
Quanta Magazine · Martin Picard’s Mitochondrial Theory of MindOn a cold December morning in 2025, Martin Picard, who studies mitochondria at Columbia University, used his own nerves to illustrate his idea that mental life has an energy cost. Standing before about 100 scientists, students, entrepreneurs, investors, and patients at a symposium he had organized, he said speaking threatened his ego, and he pointed to his pounding heart and sweating skin as evidence.
“Everything costs energy,” he said, “even subjective psychological experiences.”
Mitochondria are tiny compartments inside cells that turn food into usable energy. Picard hypothesizes they act as “orchestrators of cell function,” keeping the body’s power use inside healthy limits instead of letting the current run free.
Under that hypothesis, if the human body has what he calls a “limited energy budget,” tradeoffs will naturally arise when one “biological process consumes more than its typical share.” Competing demands “from illness, injury, or chronic stress,” in his account, can show up not just as sickness but “also as negative conscious experiences such as anxiety, brain fog, and exhaustion.”
He traces the thinking to work he began as a postdoctoral researcher. In an experiment published in 2015, he put mice through the same stressful procedure, confinement in a tube that prevented movement. Some mice had healthy mitochondria, while others carried different defects, and their bodies produced different molecular signals afterward. “If you change mitochondria, you change how the organism perceives or responds to mental stress,” Picard said.
That result shows mitochondrial biology shapes the stress response, not that low energy alone causes anxiety. Picard presents the rationing account as a hypothesis for why some people flounder while others recover, not as an established cause.
Questions people ask
What do mitochondria actually do?
Mitochondria are small structures inside almost every cell that turn food and oxygen into a chemical fuel cells can use. They also help make hormones and brain chemicals, handle calcium, and send signals that switch genes on and off. Because of that work, they influence far more than raw energy supply.
Can you improve your mitochondria?
Exercise, sleep, and steady daily rhythms are the best supported ways to support mitochondrial function. Some animal studies show that boosting mitochondrial output in the brain can reduce anxious behavior, and one commercial supplement had a similar effect in rats. There is no proven treatment yet for easing brain fog or anxiety by targeting mitochondria in people.
What does Picard mean by connecting mitochondria to consciousness?
Consciousness is the brain's ongoing awareness of itself and the world, and scientists still debate how it arises. Picard has suggested mitochondria help shape it by converting energy into signals that affect mood, stress, sleep, and perception. That broader claim remains speculative and is not accepted as demonstrated.